The Boston Red Sox enter the 2013 season with unexpected uncertainty regarding first base, after trading away slugger Adrian Gonzalez at the trading deadline this past year. Gonzalez had been inked through 2018, but his inability to give the Sox the power they had expected led to his shipment out of town. Now the position has become a significant question mark as the team moves forward.

Mike Napoli

The Sox were close to signing Mike Napoli to a three-year contract worth $39 million, but serious issues with Napoli’s hip caused the deal to be renegotiated, and the two sides settled on just a one-year deal worth $5 million, which could move up to $13 million with incentives earned by Napoli depending on the health of his hip.

Napoli is a slugger first, with an uppercut swing that has worked wonders for former Sox players at Fenway Park such as Kevin Millar and Cody Ross. Napoli has spent his entire career in the American League West, playing the last two seasons with the Texas Rangers after a five-year stint with the Los Angeles Angels.

Last year, Napoli played 108 games including 71 as a catcher. With Boston, his primary duty will be managing first base, where he’s played 125 games in his career. It should be interesting to see how his hip manages to hold up, but if Napoli can stay healthy he could provide the most dangerous bat in the entire Sox lineup.

The 31-year old has hit at least 20 home runs in each of the last five seasons, including a career-high 30 long balls back in 2011. His batting average is much less predictable, as a career .259 average is positively influenced by 2011 when he also hit .320/.414/.631, by far the strongest season of Napoli’s career. If the Red Sox can anything close to that production, it should be a great ride.

Mauro Gomez and Lyle Overbay

Of course, there’s always the chance that something does go wrong with Napoli’s hip and the Sox forced to put him on the disabled list for the lengthy period of time. If that turns out to be the case, the likely short term replacement would have to be Mauro Gomez, who saw more time than most Sox fans would like at first base last year following the Gonzalez trade.

At age 28, Gomez isn’t the young prospect looking for a chance to bloom. Still though, that doesn’t mean he wouldn’t be an adequate replacement for Napoli in the worst-case scenario. Gomez played in 37 games last season (most meaningless), hitting a solid .275 with a pair of home runs and 17 runs knocked in. He’s certainly not someone to pencil in every day in the middle of the order but it should be interesting to see what his role develops into as the season progresses.

Similarly, the team could call upon the services of veteran Lyle Overbay, who signed a minor league deal with the Red Sox after seeing a significant drop in production over the last two years with Pittsburgh, Arizona, and Atlanta. Still, there’s always a chance the 36-year old bounces back and makes an impact on the Boston roster.

David Ortiz

The Sox will have to use David Ortiz differently in 2013 with the new schedule format, which eliminates the chunk of time when virtually all teams play interleague games and instead spreads those games out over the course of the entire season to accommodate the shift of the Houston Astros to the American League.

I’d expect the Sox to at least once use a lineup against a National League team that includes Napoli serving as the catcher and Ortiz on first, though the need to keep him in the batting order could be far less significant if his production finally tails off in 2013. And after the end to last season when Ortiz’s heel sidelined him for nearly the entire final two months of the year, the chance seems more likely than ever before.

Of course, Ortiz and the Red Sox did just come together on a two-year contract worth $26 million, $11 million of which will be paid to the designated hitter in 2014. So maybe the heel really has checked out, and Big Papi will get back to mashing the ball like he was before the injury. Either way, Ortiz will spend a little bit of time at first base, while playing nearly every other day at the designated hitter spot.

Whether or not Napoli and Ortiz can stay healthy in 2013 is the biggest question facing the Sox with regards to first base and DH, but if they don’t the team could be scrambling to find adequate replacements during the year.